Operators’ Guide to Trace Elements in Anaerobic Digestion
The Operators’ Guide is intended for use by industry stakeholders, decision-makers and digester operators in navigating the topic.
The subject is the application of trace elements, and metals (TMs), and supplementation regimes in anaerobic waste-conversion biotechnologies, such as biogas digesters. TMs are dosed to anaerobic digesters to boost biological activity and to increase biogas production rates. Little is understood about the concentrations and dosing strategies best suited to sustained supplementation and stable performance in anaerobic biotechnologies.
A range of companies offer proprietary blends of trace metals for supplementation of anaerobic digesters. Very little joined-up information is available on the concentrations of individual TMs best suited to improved digester performance. Moreover, typically no attention whatsoever is paid to the bioavailability of TMs dosed to digesters i.e. despite high concentrations, TMs may not be available for uptake by the microorganisms underpinning the digestion process.
Based on extensive engagement with a range of stakeholders throughout the course of the recent EU COST Action on ‘The ecological roles of trace metals in anaerobic biotechnologies’, and particularly on feedback from industrial partners, it is clear that such a guide is needed by the operators of anaerobic digesters.